MR-9 Battery Adapter

[Walt in Chicago]

Is there a technique to get the battery out of an MR-9 adapter? I tried prying it out with an Xacto knife but had no luck.

 

[koraks]

Welcome to Photrio!
I understand we're talking about this adapter: https://www.kantocamera.com/english/adapter/adapter_en.html
I'd expect something like a small watchmaker's screwdriver should do the trick.

 

[Walt in Chicago]

Welcome to Photrio!
I understand we're talking about this adapter: https://www.kantocamera.com/english/adapter/adapter_en.html
I'd expect something like a small watchmaker's screwdriver should do the trick.

I first bought a couple of the less expensive, non voltage reducing ones, which are adequate for some equipment. I then bought a couple of the Kanto ones for a light meter, but am having trouble getting the batteries out of the non-Kanto ones, they snap in place and are hard to remove.

 

[koraks]

Yes, I understand. I don't have this adapter, but as said, I'd expect that you should be able to pry out the battery with a small watchmaker's screwdriver. An exacto knife may work as well, but there's the risk of breaking the knife's point. You could also try a pair of fine-nosed pliers; grip the edge of the cathode of the battery and try to pull it out that way.

 

[P C Headland]

I first bought a couple of the less expensive, non voltage reducing ones, which are adequate for some equipment. I then bought a couple of the Kanto ones for a light meter, but am having trouble getting the batteries out of the non-Kanto ones, they snap in place and are hard to remove.

The non-voltage drop ones I have have a small hole in the centre that you can poke a small drill bit (or similar) through.

 

[Hassasin]

Rubber glove, twist out of the hole.

 

[Walt in Chicago]

The non-voltage drop ones I have have a small hole in the centre that you can poke a small drill bit (or similar) through.

The ones I have don’t have the hole

 

[ic-racer]

Drill the hole.

 

[chuckroast]

The ones I have don’t have the hole

When you get the battery out, take time to drill one

 

[MattKing]

Put them in the freezer, and then see if that helps.
Warm them up, then see if that helps.
Try a larger pair if tweezers, to see if gripping on both sides of the battery helps.
Try prying the battery out under water.

 

[Laurent]

When you get the battery out, take time to drill one

If the battery's dead, I'd even drill (very) carefully the adapter so that the dead battery can be pushed away. I don't think the risk is too high, at least I'd be relaxed doing this on my equipment

 

[drboone]

Drill the hole.

The voltage drop version has some electronic component(s) inside the shell. Do you KNOW where those are?

 

[Hassasin]

I suggested rubber glove because that always worked for me with these adapters. Simple friction / twisting motion free it up enough. By that I meant push down into the battery just enough to allow it to spin around. If if does not spin, what @koraks is suggesting should still work.

Another tool would be strong yet small neodymium magnet.

 

[xkaes]

Stick a piece of gorilla tape on the battery. Then pull it out.

 

[wiltw]

I first bought a couple of the less expensive, non voltage reducing ones, which are adequate for some equipment. I then bought a couple of the Kanto ones for a light meter, but am having trouble getting the batteries out of the non-Kanto ones, they snap in place and are hard to remove.

The non-Voltage-conversion so-called 'MR-9' have to pemit air into the cell, so maybe you can find a pointed tool that you can push into the hole to force the cell out of the adapter body?!

 

[ic-racer]

The voltage drop version has some electronic component(s) inside the shell. Do you KNOW where those are?

Actually I have never used those; without knowing exactly what they are. Diode? Voltage regulator?

 

[koraks]

Actually I have never used those; without knowing exactly what they are. Diode? Voltage regulator?

AFAIK it's just a single Schottky diode with an appropriate voltage drop.

 

[BobUK]

Rubber gloves on to protect yourself from chemicals, then pierce the top of the battery with a small drill.
Use a home made hook to pull the battery out.

I use old bicycle spokes ground to a pointed taper, then bent into a small hook shape to unhook small helical springs in small machinery like typewriters.

Years ago a similar hook was used to button up the fine buttons on shoes. The name still survives as the spring pullers are called "Button Hooks."

So drill the hole in the battery, then hook the old cell out with a button hook.

 

[ic-racer]

AFAIK it's just a single Schottky diode with an appropriate voltage drop.

I wasn't sure because I did not think the appropriate diodes came in surface mount. I have only used glass diodes. Are you able to identify these surface mount components? BAT54J and BAS70J ?

 

[ic-racer]

None of the above look like this, which is what it should have, in my opinion. Mabye I'm missing something. I have never taken one apart.

 

[koraks]

I wasn't sure because I did not think the appropriate diodes came in surface mount.

They do.

Are you able to identify these surface mount components? BAT54J and BAS70J ?

Depends on the manufacturer, but often they're not reliably identifiable. The types you mention are also not an exhaustive list of suitable diodes.
Having said that:

I'm 99.9% certain these are SMD SOD package diodes.

This one may be a diode, but it's also possible that it's a voltage regulator. If it's the latter, I would expect to find two small ceramic capacitors somewhere near as well, and given their absence, it's more likely that this, too, is an SMD diode.

None of the above look like this, which is what it should have, in my opinion.

YMMV; plenty of people will argue that a simple series diode will be adequate. I expect that these adapters use one, and not the linear regulator you've shown. The regulator is a more fancy solution and arguably better in some ways except probably leakage current (=battery lifetime).

 

[xkaes]

My biggest "problem" is keeping the A76 batteries in the adapter -- not getting them out. Since mine all look the same -- just like the ones in the first pictures -- I assume they were from the same manufacturer. Maybe some are made tighter than others. I still think a small piece of tape will get a stubborn battery out. All I use is gravity.

 

[MattKing]

My biggest "problem" is keeping the A76 batteries in the adapter -- not getting them out. Since mine all look the same -- just like the ones in the first pictures -- I assume they were from the same manufacturer. Maybe some are made tighter than others. I still think a small piece of tape will get a stubborn battery out. All I use is gravity.

You wouldn't normally want to use an A76 battery in most of these. You would want to use a silver oxide battery in the adapters that drop the voltage, or a hearing aid/zinc air battery in the ones that don't.

 

[ic-racer]

Thank you Koraks for looking at those.

 

[xkaes]

You wouldn't normally want to use an A76 battery in most of these. You would want to use a silver oxide battery in the adapters that drop the voltage, or a hearing aid/zinc air battery in the ones that don't.

Last time I checked, "A76" batteries (I use the term generically) were available in silver oxide -- just as the 386 is available in alkaline. Apparently, I'm not the only one: using them:

MR-9 Adapter 1.55V to 1.35V

Has anyone had any experience with this adapter? I recently purchased one and prior to install it in one of my cameras I tried to measure the voltage with a voltimeter: But I cannot see such voltage reduction. Looking carefully at the manufacturer site...

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